To study the chemical constituents of Alchornea trewioides, silica gel column chromatography, Sephadex LH-20, reverse phase ODS column chromatography, MCI and semi-preparative HPLC were used to separate the 95% EtOH extract of the root of Alchornea trewioides. The structures were elucidated on the basis of spectroscopic studies including ESI-TOF-MS, 1H NMR, 13C NMR, HSQC and HMBC. Eight phenolic acids were obtained and identified as 1-O-galloyl-6-O-vanilloyl-beta-glucose (1), gallic acid (2), ethyl gallate (3), syringic acid (4), glucosyringic acid (5), erigeside C (6), 3, 4-dimethoxyphenyl-(6'-O-alpha-L-rhamnosyl)-beta-D-glucopyranoside (7) and 3, 4, 5-trimethoxyphenyl-(6'-O-galloyl)-O-beta-D-glucopyranoside (8). Among them, compound 1 is a new compound, compounds 4-8 are isolated from the genus Alchornea for the first time, and the others are isolated from the plant for the first time.

Objective To retrospectively investigate the endoscopic characteristics and pathological features of colorectal polyps in over-aged patients (≥80 years). Methods The 1617 colonoscopies performed between January 2006 and December 2010 were enrolled in our retrospective analysis. The detection rate, size, location, form and pathological feature of polyps in 150 over-aged patients were investigated, and they were compared with those in 832 young patients (＜60 years) and 635 old patients (60-79 years) with colorectal polyps. Results The detection rate of polyps was 62.0% in over-aged group, and was significantly higher than in young group and old group (30.2% and 48.7%, respectively, χ2=56.58 and 8.64,both P＜0.001). The malignant transformation rate of ascending colon polyp was 5.4% in over-aged group, and was significantly higher than in young group (1.2%, χ2=4.90, P＜0.05), but there was no significant difference between over-aged group and old group (3.9%, χ2=0.36, P＞0.05). There were no statistical differences in canceration rate, polyp diameter, morphology and adenomatous polyp rate among the three groups. The malignant transformation rate was significantly increased in adenomatous polyps with diameter over 2 cm, but didn't reach statistical significance. Conclusions The polyp detection rate is noticeably higher in the over-aged than in the old and the middle-aged, and the malignant transformation probability is also increased. The colonoscopy indications in the high risk age groups should appropriately be broadened, they should receive regular intervals follow-up, and undergo polypectomy in time if necessary.

To improve the quality of experimental teaching,investigating the independent design experiments are carrying out in preventive medicine by public health experimental teaching center in our school.We take preventive medicine professional as an example,and besides the classical basis experiments,some experiments are verification project at present,in which students are not strongly interested.On the basis of the integration of the classic experiments,according to the national standard of the experimental method,we are trying to carry out part of the independent design experiments to meet the needs of students learning.The effect of those independent design experiments shows that it is appropriate carrying out independent design experiments on the basis of the existing classical experimental project in preventive medicine experimental teaching,to a certain extent,which will stimulate students' learning interest and enhance their sense of achievement.This study is conducive to the cultivation of medical students' innovation,independent thinking,analysis and problem-solving ability,practical ability and teamwork spirit.

To examine whether or not the regulatory sequence of chicken ovalbumin gene can drive transgene expression specifically in hen oviduct, the authors constructed an oviduct-specific expression vector (pOV), containing 3.0 kilobases (kb) of the 5'-flanking sequence and 3.0 kb of the 3'-flanking sequence of the chicken ovalbumin gene. Jellyfish green fluorescence protein (EGFP) reporter gene and bacterial LacZ reporter gene were respectively inserted into the downstream of the 5'-regulatory region.The recombinants were named as pOVEGFP and pOVLacZ. Two transfer systems, in vitro and in vivo, were used to verify the function of the vector. In vitro, the plasmid DNA pOVEGFP and pEGFP-N1 were transfected respectively by the polyethyleneimine procedure into the primary chicken oviduct epithelium (PCOE) and fibroblasts cells isolated from laying hens. In vivo, the recombinant vector pOVLacZ was injected into egg-laying hens via wing vein and the tissues were collected for RT-PCR analysis.The results showed that expression of pEGFP-N1 was achieved at low level in oviduct epithelial cells and at high level in fibroblasts, but that the recombinant vector was not expressed in both cells. RT-PCR analysis showed that the LacZ gene was transcribed in the oviduct, but not in the heart, liver, kidney and spleen of the injected hens. Accordingly, the ?-galactosidase activity was only detected in the oviduct magnum (116.7 mU/ml) and eggs (16.47 mU/ml). These results indicated that the cloned regulation regions of chicken ovalbumin gene could drive exogenous gene expression specifically in the oviducts of hens. In vivo gene injection via wing vein may serve as a rapid production system of recombinant proteins in chicken eggs. In addition, the cultured primary oviduct cells from laying hens were not efficient temporary expression systems for analyzing the function of regulating elements of ovalbumin gene.

Objective: To study the role of activating transcription factor 2 (ATF-2) in the growth of mandibular condyle cartilage. Methods: Primary chondrocytes of condyle were cultured. Expression plasmid of ATF-2 and plasmid bcl-2 promoter were transfected into chondrocytes. Luciferase assay and Western blot were used. Results: The absence of ATF-2 in mandibular condyle chondrocytes resulted in a decline in bcl-2 promoter activity, reduction in bcl-2 protein level. Conclusion: The results strongly imply that ATF-2 is required for adequate bcl-2 expression, and play a significant role in controlling growth plate chondrocyte progression.

Objective To analyze the relationship between the clinical features of hepatoblastoma and serum alpha-fetoprotein level.Methods We did a retrospective study in 74 cases into the relationship of clinical stages,treatment,prognosis,and AFP value in hepatoblastoma.Results In Stage Ⅰ and Ⅱ patients,the average AFP was (36 333 ± 13 782) ng/ml and in Stage Ⅲ and Ⅳ,the average AFP was (78 346 ± 27 956) ng/ml,P ＜ 0.05.68 patients received preoperative chemotherapy with alpha-fetoprotein determinations before and after chemotherapy respectively.In 44 cases AFP decreased ＞ 50％ after chemotherapy,and in 20 cases AFP declined ＞90％,while in 13 cases AFP increased after chemotherapy.15 cases had serum AFP measured on the first postoperative day,among them 10 cases had a ＞ 50％ AFP decline,3 cases had a ＜ 50％ AFP decline,while in 2 cases AFP value increased.52 cases were postoperatively followed-up,with overall 3 year-survival rate of 86.5％ ; 7 cases recurred,4 died.The average preop AFP level in 7 recurred cases was (27 060 ± 3 569) ng/ml,while the average preop AFP level in those of 3-year recurrence-free was (29 865 ± 5 867) ng/ml,P ＞ 0.05.Only 57％ tumor recurred cases had back to normal AFP level within one month postop,while 89％ long term survivals reported normal range of AFP during that period,P ＜ 0.05.Conclusions Serum AFP level in patients with hepatoblastoma is related to the course of disease.It can be used to estimate the effect of clinical chemotherapy.The speed of alpha-fetoprotein decline postop can be used as an indicator of prognosis.The postoperative normal AFP level within 4 weeks predicts a favorable prognosis.

Objective To evaluate the effects of different concentrations of chloroprocaine on KCNQ2/Q3 channel currents in HEK2936 cells.Methods Human embryonic kidney (HEK293) cells served as an expression system.KCNQ2 and KCNQ3 cDNAs and green fluorescent protein were transfected into HEK293 cells by using lipofectamine.The KCNQ2/Q3 currents were recorded by using the whole-cell patch-clamp technique.Part Ⅰ The transfected HEK293 cells were randomly divided into 4 groups (n =11 each):control group,and 1,10 and 100 mmol/L chloroprocaine groups.The KCNQ2/Q3 channel currents produced by different concentrations of chloroprocaine were recorded under different holding potentials (-40,0 and 40 mV) and the action time was 1 min.Part Ⅱ The transfected HEK293 cells were randomly divided into 2 groups (n =5 each):control group and 10 mmol/L chloroprocaine.The KCNQ2/Q3 channel currents were recorded under different holding potentials (-80-30 mV)and the action time was 1 min.Different test potentials were normalized and fitted to Boltzmann function,and KCNQ2/Q3 channel Ⅰ-Ⅴ curve was then obtained.The activation and deactivation currents were both fitted to a single exponential function and the time constants for current activation and for current deactivation were calculated.Results Part Ⅰ When the holding potential was 40,0 and-40 mV,the suppression rate of KCNQ2/Q3 channel currents in HEK293 cells was higher in 1,10 and 100 mmol/L chloroprocaine groups than in control group (P ＜0.05 or 0.01).Part Ⅱ Compared with control group,the time constant for the current activation at 0 mV of holding potential was prolonged,the time constant for the current deactivation was shortened when the holding potential was-80 mV,and the half-activation voltage of KCNQ2/Q3 channels was increased,the activation curve shifted to the depolarized potentials,and KCNQ2/Q3 channel Ⅰ-Ⅴ curve slope was decreased in 10 mmol/L chloroprocaine group (P ＜ 0.05).Conclusion Chloroprocaine concentration-dependently suppresses KCNQ2/Q3 channel currents in HEK2936 cells.The KCNQ2/Q3 channel is closed in advance due to KCNQ2/Q3 channel opening delay induced by chloroprocaine thus decreasing the activity of KCNQ2/Q3 channels.

·AIM: To determine whether a combined scleral buckle and pars plana vitrectomy, as a primary surgery, owns any advantage over a single scleral buckling in pseudophakic and aphakic retinal detachments.·METHODS: Thirty consecutive pseudophakic/aphakic retinal deachments were included in this retrospective study. Each patient underwent combined scleral buckle and pars plana vitrectomy, and was followed up for 3 to 14 months. Patients were examined with respect to anatomic reattachment, visual acuity improvement, and surgical complications.·RESULTS: All eyes were anatomically reattached after the first operation. All patients had an increase in their visual acuity, and there were no complications attributable to the vitrectomy procedure.·CONCLUSION: A combined surgery for primary pseudophakic/aphakic retinal detachments offers significant benefits to scleral buckling alone. The improved uccess rate is contributing to the function of vitrectomy, which improves peripheral visibility and reduces the occurrence of proliferative vitreoretinopathy (PVR).

AIM: To investigate the characteristics and surgical management of retinal detachment (RD) after laser-assisted in situ keratomileusis (LASIK) in myopia.METHODS: Documents of patients with RD observed in 18342 eyes (9 598 patients) who underwent LASIK were retrospectively reviewed. None of the patients had history of corneal or other diseases before LASIK and preoperative fundus examination was performed. Patients were followed for a mean of 20 months and the clinical features of the eyes which developed RD after LASIK were investigated.RESULTS: Six patients including 2 males and 4 females developed RD, and the incidence of RD after LASIK was 0.33‰. Mean pre-LASIK myopia in these 6 eyes was 9.33D.None of these eyes had prophylactic treatment history of any retinal lesions. Mean time interval between LASIK and RD development was 9.2 months. All RDs happened spontaneously and were managed with vitrectomy and other techniques.Retinal reattachment was achieved at the first retinal detachment surgery in all 6 eyes (100%) at mean follow-up of 9.3months.CONCLUSION: RD after LASIK is not common. The study suggests no cause-effect relationship between RD and LASIK procedure in myopic eyes. However, clinicians should still be aware of retinal pathology in patients undergoing LASIK.

AIM: To assess the efficacy and safety of prophylactic laser photocoagulation for retinal breaks before laser in situ keratomileusis (LASIK) in myopic eyes.METHODS: From April 2000 to April 2004, totally 1 845 eyes ( 1 233 patients ) requesting LASIK had a fundus examination with indirect ophthalmoscopy before the surgery. They were divided into two groups according to the presence (Group 1) or absence of retinal breaks (Group 2). All patients with retinal breaks, though they were asymptomatic, underwent prophylactic laser photocoagulation to seal the breaks before LASIK.RESULTS: Patient age ranged from 18 to 43 ( 25.3±5.7) yaers old. Mean preoperative spherical equivalent refraction (PSER) was -7.44± 2.13 D (range, -1.50 to -14.50 D). Retinal breaks were identified and treated in 37eyes (2.05%) of 32 patients;1 808 eyes of 1 201 patients had no retinal breaks. No statistical difference was found in age ( P ＞0.05) or gender (P ＞0.05) between the two groups. Significant difference of PSER was noted between Group 1 (-9.41± 4.15D) and Group 2 (-7.52±3.71D) (P＜0.05). During a mean 14mo follow-up, none of the patients developed retinal detachment.CONCLUSION: The efficacy and safety of prophylactic laser photocoagulation for retinal breaks was confirmed.Retinal breaks should be identified and treated by photocoagulation in eyes before LASIK for myopia.